As electronics devices are being extensively downsized, components constituting them are required to be assembled in a harmonized and packed manner and to save spaces. In order to meet such a requirement, more and more electronic devices become very difficult to be assembled on an existing flat printed circuit board like a glass epoxy printed circuit board. The Molded Interconnect Device (MID) technology has been proposed in order to overcome the foregoing problem. Specifically, the Microscopic Integrated Processing Technology (MITPTEC) has been proposed in order that micro fabricated electronic circuits can be three-dimensionally mounted on a molded circuit board. Refer to Japanese Patent Laid-open Publication Hei 7-66533, for instance.
The Microscopic Integrated Processing Technology is applicable to fabricating appliances in which electric circuits, electric mechanical functional components and so on are assembled on a molded circuit board. Specifically, microscopic three-dimensional circuits can be fabricated by using lasers. Further, circuit patterns on printed circuit boards can be freely modified.
Usually, the following appliances are put on or hooked on users' ears, and should be very small; a hearing aid which collects sounds from an external source, amplifies them, and output them to a user; a radio receiver which amplifies voice signals superimposed on transmitted radio waves and outputs them as voice sounds; a playback unit which reads stored voice signals from a memory and outputs them as voice sounds. The foregoing appliances are strongly demanded to be small by users.
There is a problem that it is very difficult to downsize such appliances when flat printed circuit boards are used. Further, functional components have to be connected using lead wires, which complicates an assembling process. Still further, incorrect wiring or disconnections may lead to problems which will result in reduced quality or reliability of appliances.
The present invention has been contemplated in order to provide a voice output unit which can overcome problems of the related art, and can simplify an assembling process, improves the quality and reliability, and is small as possible.